#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<tgmath.h>
int main()
{
	char a[80] = { 0 };
	int i = 0;
	char b[80] = { 0 };
	char c;
	while (scanf("%c", &c))
	{
		if (c == '\n')
			break;
		a[i] = c;
		i++;
	}
	int n = 0;
	for (int j = 0; j < i; j++)
	{
		if (a[j] >= 'A' && a[j] <= 'Z')
		{
			int flag = 0;
			for (int k = 0; k <= j; k++)
			{
				if (b[k] == a[j])
				{
					flag = 1;
					break;
				}
			}
			if (flag == 0)
			{
				b[n] = a[j];
				n++;
			}
		}
	}
	for (int m = 0; m < n; m++)
	{
		printf("%c", b[m]);
	}
	return 0;
}
